THE PROCESSES OF REFINING CRUDE PETROLEUM enormous supplies of petroleum in this country never had any great industrial value until some method of purification or refining was in vented. The early attempts to use the crude oil for domestic lighting purposes in various places were invariably unsuccessful, on account of the sooty, smoking flame, and the extremely disagreeable, nauseous odor. Use as an illuminant was the only avenue of development which seemed to offer any real possibilities, but it was absolutely necessary that the quality of the oil should be improved by the removal of these objectionable features, if its use were to become general.
Purification of petroleum was done in a rough way many years before the modern process was perfected, but never on a very important scale. The medicinal oils used in European countries two centuries ago were generally subjected to some process of distillation or filtration. Refined illu minating oil from the Galician districts was intro duced in the early part of the last century, and soon after that time filtering through charcoal was tried in this country to remove the odor and im prove the general appearance of the crude oil. The first important refining plant in the world, however, was probably erected in the Baku dis trict about 1823. It consisted of an iron still having a capacity of forty buckets, and said to give about sixteen buckets of so-called " white naphtha " from each charge. This refined oil found a ready sale at the great Russian fair at Nishni Novgorod, presumably to be used in lamps.
Petroleum refining in this country began in a small way about 1855, with Kier's experiments to turn his medicinal oil to some more valuable use. The manufacture of so-called "paraffine oils" from coal and shale had increased so rapidly in the decade following 1850 that there were some fifty or sixty establishments in the eastern part of the United States when Drake's well was opened. Kier's results had already shown clearly enough that paraffine oils could be secured more easily from petroleum than from coal or shale, and more cheaply also jf the supply of petroleum were large enough. The prospect of securing petro leum in large quantities by following Drake's ex example made the entire shale oil industry totter. The owners of the refineries, many of which were then only fairly started, saw themselves facing ruin, until a simple and easy salvation appeared in converting their plants into petroleum refineries.
Thus, the latter industry was able to profit imme diately from the existence of this large number of ready-made establishments.
Kier's first attempts at refining petroleum had given him a "carbon oil" distillate, distinctly su perior to the crude oil, but far from being perfect. The strong odor still persisted and brought a storm of complaints from the consumers. General dissat isfaction was expressed also on account of the rapidity with which the oil turned black, and on account of the formation of a hard crust on the wick which interfered with the free burning of the flame. As a result the "carbon oil" gained favor slowly, despite the fact that an army of canvassers and selling agents spread over the country to boom its use. Something had to be done to place petro leum oil on as satisfactory a basis as were the shale and coal oils. Distillation alone would evidently never suffice. Chemical treatment to purify the products after distillation was tried and soon dem onstrated that successive manipulations with solu tions of alkali and acid would remove the chief ob jectionable features. These improvements, already familiar abroad, had been introduced here about the time Drake went to the oil regions. Therefore, as soon as his well was struck, the refining of petro leum was in a condition to expand and drive the shale-oil industry out of existence in short order.
The most important process in the refining of petroleum, as it is carried on to-day, consists essen tially of two parts : first, heating the oil in a still until it vaporizes in the same way as boiling water passes into steam ; and second, condensing these vapors just as steam condenses on cold objects. The successful separation of the different products depends on the fact that each of the many com pounds. composing crude oil has its own particular boiling point, and thus allows gradual heating to carry on the process of division, or fractional dis tillation, as it is called. The stills where the crude oil is heated, the condensers where the vapors of successive divisions are returned to the liquid form, and the tanks for storing the refined products, therefore, represent the important parts of the skeleton of every refinery.